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The output parameter can take the following strings:
“none”“hdmi”- “HDMI-1” "HDMI-2" "HDMI-3" or "HDMI-4"
“usb”“spdif”"analog"“analog:N”(N specifies the port enumeration, which is useful for models with multiple analog-audio ports; you can also use"analog:1"to specify the analog output on a model with a single analog-audio port)"earc"(AU335 only)Support for multiple USB outputs using the USB port naming terminology. See roDeviceInfo-getusbtopology
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